Abstract

The photolysis of 2,4-dinitrobenzenesulphenyl esters affords carboxylic acids in high yield. The initial step in this photolysis has been defined. The photolysis of phenolic esters has been further investigated. The esters of fluorene-9-carboxylic acid and xanthen-9-carboxylic acid afford reasonable yields of phenols with concomitant fragmentation of the acid residue. The potential advantages of protecting groups which can be removed photochemically under neutral conditions have been emphasised. A preliminary report of some aspects of our work has appeared.